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<a name="boost.signals2.mutex"></a><div class="titlepage"></div>
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<h2><span class="refentrytitle">Class mutex</span></h2>
<p>boost::signals2::mutex — A header-only mutex which implements the Lockable concept of Boost.Thread.</p>
</div>
<h2 class="refsynopsisdiv-title">Synopsis</h2>
<div class="refsynopsisdiv"><pre class="synopsis"><span class="comment">// In header: &lt;<a class="link" href="../../signals2/reference.html#header.boost.signals2.mutex_hpp" title="Header &lt;boost/signals2/mutex.hpp&gt;">boost/signals2/mutex.hpp</a>&gt;

</span>
<span class="keyword">class</span> <a class="link" href="mutex.html" title="Class mutex">mutex</a> <span class="special">{</span>
<span class="keyword">public</span><span class="special">:</span>
  <span class="keyword">void</span> <a class="link" href="mutex.html#id-1_3_35_6_6_3_1_1_3_1-bb"><span class="identifier">lock</span></a><span class="special">(</span><span class="special">)</span><span class="special">;</span>
  <span class="keyword">bool</span> <a class="link" href="mutex.html#id-1_3_35_6_6_3_1_1_3_2-bb"><span class="identifier">try_lock</span></a><span class="special">(</span><span class="special">)</span><span class="special">;</span>
  <span class="keyword">void</span> <a class="link" href="mutex.html#id-1_3_35_6_6_3_1_1_3_3-bb"><span class="identifier">unlock</span></a><span class="special">(</span><span class="special">)</span><span class="special">;</span>
<span class="special">}</span><span class="special">;</span></pre></div>
<div class="refsect1">
<a name="id-1.3.35.6.7.3.4"></a><h2>Description</h2>
<p>
            The <code class="computeroutput">mutex</code> class implements the <code class="computeroutput">Lockable</code>
            concept of Boost.Thread, and is the default <code class="computeroutput">Mutex</code> template parameter
            type for signals.
            If boost has detected thread support in your compiler, the <code class="computeroutput">mutex</code>
            class will map to a CRITICAL_SECTION on Windows
            or a pthread_mutex on POSIX.  If thread support is not detected, <code class="computeroutput">mutex</code>
            will behave similarly to a <a class="link" href="dummy_mutex.html" title="Class dummy_mutex">dummy_mutex</a>.
            The header file <code class="computeroutput">boost/config.hpp</code>
            defines the macro <code class="computeroutput">BOOST_HAS_THREADS</code> when boost detects threading support.
            The user may globally disable thread support
            in boost by defining BOOST_DISABLE_THREADS before any boost header files are included.
          </p>
<p>
            If you are already using the Boost.Thread library, you may prefer to use its
            boost::mutex class instead as the mutex type for your signals.
          </p>
<p>
            You may wish to use a thread-unsafe signal, if
            the signal is only used by a single thread.  In that case, you may prefer to
            use the <a class="link" href="dummy_mutex.html" title="Class dummy_mutex">signals2::dummy_mutex</a> class as the <code class="computeroutput">Mutex</code>
            template type for your signal.
          </p>
<pre class="literallayout"><span class="keyword">void</span> <a name="id-1_3_35_6_6_3_1_1_3_1-bb"></a><span class="identifier">lock</span><span class="special">(</span><span class="special">)</span><span class="special">;</span></pre>
<p>Locks the mutex.
              </p>
<pre class="literallayout"><span class="keyword">bool</span> <a name="id-1_3_35_6_6_3_1_1_3_2-bb"></a><span class="identifier">try_lock</span><span class="special">(</span><span class="special">)</span><span class="special">;</span></pre>
<p>Makes a non-blocking attempt to lock the mutex.
              </p>
<div class="variablelist"><table border="0" class="variablelist compact">
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<col>
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<td><p><span class="term">Returns:</span></p></td>
<td><p><code class="computeroutput">true</code> on success.</p></td>
</tr></tbody>
</table></div>
<pre class="literallayout"><span class="keyword">void</span> <a name="id-1_3_35_6_6_3_1_1_3_3-bb"></a><span class="identifier">unlock</span><span class="special">(</span><span class="special">)</span><span class="special">;</span></pre>
<p>Unlocks the mutex.
              </p>
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<div class="copyright-footer">Copyright © 2001-2004 Douglas Gregor<br>Copyright © 2007-2009 Frank Mori Hess<p>Distributed under the Boost
    Software License, Version 1.0. (See accompanying file
    <code class="filename">LICENSE_1_0.txt</code> or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)</p>
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